large for dates Flashcards
what is large for date?
Symphyseal-fundal height >2cm for Gestational age
Causes of large for date?
Wrong dates
Fetal Macrosomia
Polydramnios
Diabetes
Multiple Pregnancy
(Obesity)
fetal macrosomia- what?
big baby
how is fetal macrosomia diagnosed?
USS EFW >90th centile
AC>97TH Centile
AC- abdominal circumference
EFW- estimated fetal weight
Risks related to fetal macrosomia?
-clinican + maternal anxiety
-labour dystocia
-shoulder dystocia (more with diabetes)
-PPH (post partum haemorrhage)
shoulder dystocia= babies should trapped behind pubic synphesis
problems with using USS for ESF?
-Ultrasound ESF is commonly overestimated
-USS More accurate <38 weeks
-Influenced by BMI of women (harder if higher)
-Operator dependant
Management- fetal macrosomia?
-Exclude diabetes
-Reassure
If EFW>/=5kg offer c/section
NICE Recommendation: In the absence of any other indications, induction of labour should not be carried out simply because a healthcare professional suspects a baby is large for gestational age (macrosomic).
what is polyhamdramnios?
Excess amniotic fluid
criteria for diagnosis of POLYHADRIMNIOS?
- Amniotic Fluid Index (AFI >25cm)
Deepest Pool >8cm
maternal risks for polyhadriminios?
more likely with diabetes
fetal risks for polyhadriminios?
-Anomaly (GI atrsia, cardiac, tumour)
-Monochorionic twin pregnancy
- Hydrops fetalis (Rh isoimmunisation)
-Viral infection (erythrovirus B19, Toxoplasmosis, CMV)
-Idiopathic
presentation for polyhadriminios?
Most are asymptomatic
Symptoms
-Abdominal discomfort
-Pre-labour rupture of membranes
-Preterm labour
-Cord prolapse
Signs
-LFD
- Malpresentation
- tense shiny abdomen
-inability to feel fetal parts
investigations for polyhadriminios?
DIAGNOSTIC:
Amniotic Fluid Index (AFI) >25cm
Deepest Pool >8cm
USS fetal survey to look at babys:
-lips
-stomach
Exclude risk factors:
OGTT - to exclude maternal diabetes
Serology to exclude viral infection- toxoplasmosis, CMV, Parvovir
Antibody screen
Management for polyhadriminios?
-IOL by 40 weeks
Serial USS- growth, LV, presentation
-Neonatal examination
risks in labour for polyhadriminios?
Risks during labour:
-malpresentation
-cord prolapse
-Preterm Labour
-PPH
what increases risk of multiple pregnancy?
Increased with:
-Assisted conception
-African women
-FH
-increased materanal age
-increased parity
-Tall women> small women
monozygotic- what?
splitting of a single fertilised egg
dizygotic- what?
fertilisation of 2 ova by spermatozoa
Chorionicity -what?
1 or 2 placentas
why is it important to identify monozygotic, dizygotic or chorionicity on USS?
important to determine via USS because monochorionic/monozygous twins are at higher risk of pregnancy complication
when would splitting have to occur to have monochorionic twins?
Monochorionic will occur if splitting happens after 4-7 days
investigations for multiple pregnancy?
Multiple pregnancy - confirmed at 12 weeks
-Shape of membrane and thickness of membrane (twin peak at 11-13 + 6 weeks with CRL 45-84mm)
-Fetal sex
-Chorionicity
when is the US scan to check for multiple pregnancy?
12 weeks
symptoms/ signs of multiple pregnancy?
- Symptoms
- Exaggerated pregnancy symptoms e.g. excessive sickness/ hyperemesis gravidarum
- Signs
- High AFP
- Large for dates uterus
- Mutiple fetal poles
USS confirmation at 12 weeks
complications for fetus in multiple pregnancy?
Fetal includes congenital anomalies, IUD, pre-term birth, growth restriction, cerebral palsy, twin to twin transfusion
complications for mother in multiple pregnancy?
Maternal include hyperemesis gravidarum, anaemia, pre eclapsia
complications of monochorionic twins?
Single Fetal Death
Selective Growth Restriction (sGR)
Twin-To- Twin Transfusion Syndrome (TTTS)
Twin Anaemia- P0lycythaemia Sequence (TAPS)
Abnormal Dopplers: Absent EDF (AEDF) or Reversed EDF (REDF)
at what point does splitting occur for monochorionic twins
Monochorionic will occur if splitting happens after 4-7 days
what is twin to twin transfusion
Syndrome with artery-vein anastomoses. Donor twin perfuses the recipient twin
risks of twin to twin transfusion?
More common in monochorionic/ monozygotic twins
Rare after 26/40
what is seen on USS- twin to twin transfusion?
USS:
-Oligohydramnios
-polyhydramnios (Oly-Poly)
Management- twin to twin transfusion?
Before 26/40 –fetoscopic laser ablation
> 26/40- amnioreduction /septostomy
Deliver 34-36/40
complications- twin to twin transfusion?
Untreated, TTTS has a high mortality rate for both twins, with the donor more likely to survive
* Mortality >90% with no treatment
Neurological morbidity 37% and high in surviving twin if IUD
why do both foetus in twin to twin transfusion risk developing heart failure and hydrops?
- Both foetuses are at risk of developing heart failure and hydrops
- The donor suffers high output cardiac failure as a consequence of severe anaemia and the recipient suffers fluid overload
how are conjoined twins managed?
Conjoined twins:
-MDT
-specialised centres
maangement- Monochorionic Monoamniotic?
-deliver by C/section 32-34 weeks
-higher risk of foetal death due to risk of cord entanglemnt
what what point are DCDA twins delivered?
37 to 38 weeks
what what point are MCDA twins delivered?
> 36 weeks with steroids
how are triplets delivered
cesarean
how are MCMA (monochorionic monoamniotic) delivered?
ceserean section
gestational diabetes- what?
carbohydrate intolerance resulting in hyperglycaemia of variable severity with onset or first recognition during pregnancy
whats different in gestational diabetes compared to regular?
- Increases insulin requirements
- N&V can precipitate DKA
- Ketosis more common
- Diabetic retinopathy worsens especially after rapid control of diabetes
Diabetic Nephropathy can worsen
RISKS- gestational diabetes
-BMI above 30 kg/m2
-previous macrosomic baby weighing 4.5 kg or above
-previous gestational diabetes
-family history of diabetes (first‑degree relative with diabetes)
-minority ethnic family origin with a high prevalence of diabetes
investigation for gestational diabetes?
Screening first line= oral glucose tolerance test (OGTT)
Fasting >=5.1 mmol/l
2 hour >=8.5 mmol/l
who is screened for gestation diabetes?
OGTT is used in patients with risk factors for gestational diabetes, and also when there are features that suggest gestational diabetes:
-Large for dates fetus
-Polyhydramnios
-Glucose on urine dipstick
RISKS:
-BMI above 30 kg/m2
-previous macrosomic baby weighing 4.5 kg or above
-previous gestational diabetes
-family history of diabetes (first‑degree relative with diabetes)
-minority ethnic family origin with a high prevalence of diabetes
how often should women with gestational diabetes check blood glucose?
measure blood glucose 4x daily:
-fasting (pre breakfast)
-postmeals (1 hour or 2 hours post meal)
-before bed
glycaemic targets- gestational diabetes?
Fasting 3.5-5.5mmol/l
1hr <7.8mmol/l
2hr <6.4mmol/l
At what estimated fetal weight should C section be done for gestational diabetes?
> 4.5kg
what risk does breast feeding have - diabetes?
hypoglycaemia
what risk does breast feeding have - diabetes?
hypoglycaemia
